Cannabidiol (CBD), one of the major phytochemicals in marijuana, has become a popular ingredient in dietary supplements, beauty products and beverages, with claims that the compound improves health and treats ailments ranging from insomnia to cancer. Although research on CBD is accelerating, medical evidence is still lacking for many of these claims, reports an article in Chemical & Engineering News (C&EN), the weekly newsmagazine of the American Chemical Society.

Proof of a therapeutic effect of CBD is strongest for rare seizure disorders, writes Senior Editor Bethany Halford. Three clinical trials enrolling more than 500 patients have shown that a CBD oral solution, taken with other medications, halved the number of seizures in 40 percent of children and young adults with two rare forms of epilepsy. These trials, which were conducted by the British firm GW Pharmaceuticals, convinced the U.S. Food & Drug Administration to approve Epidiolex, a CBD drug made by GW, for sale on the U.S. market. Unlike the better-known marijuana component tetrahydrocannabinol (THC), CBD is not psychoactive.

Despite these promising results, CBD is no miracle cure. Some patients in the studies did not respond to the drug, and others experienced side effects such as sleepiness, diarrhea and elevated liver enzymes --- a possible sign of liver damage. To figure out why some people benefit from CBD and others don't, and what other diseases might be treated, scientists are working to unravel the mechanism behind the compound. In addition to these basic research studies, more than 40 clinical trials of CBD are being conducted for a wide range of disorders. Once these studies are complete, doctors and patients will be better able to distinguish hope from hype, Halford says.

The American Chemical Society, the world's largest scientific society, is a not-for-profit organization chartered by the U.S. Congress. ACS is a global leader in providing access to chemistry-related information and research through its multiple databases, peer-reviewed journals and scientific conferences. ACS does not conduct research, but publishes and publicizes peer-reviewed scientific studies. Its main offices are in Washington, D.C., and Columbus, Ohio.